* default PHY address which is zero to a MAC when it found
* a MAC has no PHY address, we give a PHY address to XFI
* MAC, and should not use a real XAUI PHY address, since
* default PHY address which is zero to a MAC when it found
* a MAC has no PHY address, we give a PHY address to XFI
* MAC, and should not use a real XAUI PHY address, since